1 Field of the Invention
The present invention relates to a method of transferring and storing glass sheets, especially flat glass sheets, without scratching or damaging them, and a tray used in the method.
2. Description of the Relevant Art
Flat glass sheets are generally liable to slip on their surfaces irrespective of whether they have frosted patterns or impressed patterns on their surfaces. Therefore, when flat glass sheets are stacked or placed flatwise on a tray having a hard surface, they tend to slip on each other or the tray at the time a conveyor carrying them is started or stopped, with the result that the glass sheet surfaces may have abrasive scratches. One customary solution employed in a continuous glass sheet production facility has been to place and fix glass sheets vertically in a box-shaped pallet of iron or wood that can be disassembled, and to transfer and store the glass sheets in the pallet. This practice is however costly since the pallets used are specially designed and hence very expensive, and makes it difficult to automatize the transfer of glass sheets because manual labor is required to assemble and disassemble the pallets and the pallets must be hoisted and moved by a forklift or the like controlled by a human operator. Glass sheets are produced in different sizes to meet various desired applications. A large number of pallets must be made available in more than ten types in order to meet the dimensions of differently sized glass sheets, and provision of such pallets is costly and causes a storage problem. Since the pallets must be strong enough to withstand the large weight of glass sheets to be carried thereby, the volume and weight of an individual pallet are considerably large, making it relatively inefficient to transfer and store glass sheets.